Burnt residue including ash and hard objects is typically removed from the downwardly opening outlet of an incinerator, furnace or the like by a conveyor of the type described in U.S. Pat. No. 4,440,097 having a trough having a lower upstream portion underneath the incinerator and positioned to receive the residue therefrom and an upper downstream portion spaced therefrom in a longitudinal transport direction. A body of quenching liquid in the downstream portion of the trough serves to cool and quench the hot residue that is dumped into the trough. Respective upstream and downstream wheels at the upstream and downstream ends of the trough are rotatable about generally parallel and horizontal axes transverse of the trough and direction and support a chain having an upper stretch and a lower stretch. The trough has a longitudinal partition or floor extending between the upper and lower chain stretches and this upper stretch has pushers which drag material that lands on this floor in the transport direction up out of the body of liquid.
Such an arrangement works very well with residue that does not include massive objects, like chunks of metal or the like as can be found in the residue of burnt refuse or trash. Such hard and massive objects can fall through the body of water with enough force to dent and damage the floor of the trough. Not only does this damage the trough, but it can lead to material jamming and causing excessive tension on the chain, breaking it. If the floor is pierced or the chain broken, the entire piece of equipment must be taken out of service for repairs that are difficult at best and that always entail emptying the trough.